High ferroelectric polarization in c-oriented BaTiO₃ epitaxial thin films on SrTiO₃/Si(001)

The integration of epitaxial BaTiO₃ films on silicon, combining c-orientation, surface flatness, and high ferroelectric polarization is of main interest towards its use in memory devices. This combination of properties has been only achieved so far by using yttria-stabilized zirconia buffer layers. Here, the all-perovskite BaTiO₃/LaNiO₃/SrTiO₃ heterostructure is grown monolithically on Si(001). The BaTiO₃ films are epitaxial and c-oriented and present low surface roughness and high remnant ferroelectric polarization around 6 μC/cm². This result paves the way towards the fabrication of lead-free BaTiO₃ ferroelectric memories on silicon platforms.